In the prior art there are at least three known methods for the preparation of 2,4-dinitro-2,4-diazopentane or dimethylmethylenedinitramine hereinafter known as DMMD.
In the first of these methods two moles of methylnitramine are reacted with formaldehyde in the presence of a 90% sulfuric acid catalyst. This method according to Goodman, disclosed in the Journal American Chemical Society Vol. 75, page 3019 (1953) yields 39% DMMD. Goodman obtained the same yields when 82 and 90% sulfuric acid was used. The yield dropped to 13% when 74% sulfuric acid was used.
In a second known method one mole of 2-nitro-2-aza-1-propanol, hereinafter known as NAP, is reacted with one mole of methylnitramine using toluene as an azeotrope to remove water. In this reaction DMMD is recovered in a yield of 43%.
In the third known reaction well known in the prior art the ammonium salt of methylnitramine is reacted with chlorodimethylamine nitrate using dimethylformamide as a solvent and catalytic agent to yield DMMD and ammonium chloride. The yield of DMMD in this reaction is limited to 27% and is disclosed in Chemical Abstracts Vol. 65, entries 10483d and 10484c.
In short the low yields known in the prior art have prevented this DMMD from becoming a commercial explosive or energetic compound because of great cost associated with low yield.